1. Field of the Invention
The present invention relates to an organic light emitting display, and more particularly, to an organic light emitting display, in which the number of output lines provided in a data driver is decreased while the image is displayed with uniform brightness.
2. Discussion of Related Art
Recently, various flat panel displays have been developed, which are substituting for a cathode ray tube (CRT) display because the CRT display is relatively heavy and bulky. The flat panel displays include liquid crystal displays (LCD), field emission displays (FED), plasma display panels (PDP), and organic light emitting displays among other types.
Among the flat panel displays, the organic light emitting display includes organic light emitting diodes that emit light by electron-hole recombination. These organic light emitting displays have a faster response time than the LCDs that require a separate light source.
FIG. 1 illustrates a conventional organic light emitting display. A conventional organic light emitting display includes a pixel portion 30 including a plurality of pixels 40 formed in an intersection region of a plurality of scan lines S1 through Sn and a plurality of data lines D1 through Dm. A conventional organic light emitting display also includes a scan driver 10 to drive the scan lines S1 through Sn; a data driver 20 to drive the data lines D1 through Dm; and a timing controller 50 to control the scan driver 10 and the data driver 20.
The scan driver 10 generates scan signals in response to scan control signals SCS transmitted from the timing controller 50, and supplies the scan signals to the scan lines S1 through Sn in sequence. Further, the scan driver 10 generates emission control signals in response to the scan control signals SCS, and supplies the emission control signals to emission control lines E1 through En in sequence.
The data driver 20 generates data signals in response to data control signals DCS transmitted from the timing controller 50, and supplies the data signals to the data lines D1 through Dm. The data driver 20 supplies the data signal corresponding to one horizontal line per horizontal period to the data lines D1 through Dm.
The timing controller 50 generates the data control signals DCS and the scan control signals SCS in response to external synchronization signals. The data control signal DCS is transmitted to the data driver 20, and the scan control signal SCS is transmitted to the scan driver 10. Further, the timing controller 50 rearranges external data Data and supplies it to the data driver 20.
The pixel portion 30 receives external first power from an external first power source line ELVDD and external second power from an external second power source line ELVSS. The first power from the first power source line ELVDD and the second power from the second power source line ELVSS are supplied to each pixel 40. Each pixel 40 receives the data signal and displays an image corresponding to the data signal. Further, the emission time of the pixels 40 is controlled by the emission control signals.
In the conventional organic light emitting display, the pixels 40 are placed in the intersection regions of the scan lines S1 through Sn and the data lines D1 through Dm. The data driver 20 includes m output lines to supply the data signals to m data lines D1 through Dm. That is, the data driver 20 of the conventional organic light emitting display should have the same number of output lines as the number of the data lines D1 through Dm. To have m output lines, the data driver 20 needs to include a plurality of data integrated circuits that increase the production cost. Particularly, as the resolution and the size of the pixel portion 30 increase, the number of output lines of the data driver 20 increases. Thus, the production cost of the organic light emitting display is increased.
Therefore, there is a need for organic light emitting displays that require fewer output lines and therefore fewer data integrated circuits in their data driver. There is also a need for an organic light emitting display that displays a stable image with high uniformity.